A seemingly routine walk for a dog owner in Andover, Massachusetts, turned into a harrowing lesson on how the nation's opioid crisis can harm our pets, too.

According to The Boston Globe, a man named Peter Thibault was walking his family's yellow Labrador puppy Zoey in late October when the 3-month-old canine started sniffing around a pack of cigarettes on the ground.

The curious pup put the pack in her mouth, and Thibault quickly got it out. But within two minutes, Zoey collapsed, the Globe reported.

When Zoey's eyes rolled in the back of her head and her breathing was labored, Thibault rushed the pup to Bulger Veterinary Hospital.

The hospital's medical director, Dr. Krista Vernaleken, said that Zoey's symptoms suggested an opioid overdose. The hospital believes that fentanyl, a dangerous synthetic opioid, had likely been placed in the cigarette box.

To ensure that Zoey would survive, the veterinarian on call at Bulger gave the dog naloxone, an overdose reversal drug. It worked: Zoey survived the terrifying ordeal, and the Thibault family's cautionary tale has opened the eyes of pet parents everywhere.

Fentanyl, which took the lives of 64,000 people in 2016 alone, "does not have an odor that makes it easily identifiable when smelling it," according to Dr. Paula Johnson, a clinical assistant professor at Purdue University College of Veterinary Medicine.

That means the drug, though very common, is not easily identifiable. "What is important to consider is that fentanyl is often utilized to cut or mix with other drugs," Johnson told petMD. "Not only would this change the odor, it would also change the appearance."

Zoey showed common signs of a fentanyl overdose, which include loss of balance and tongue sticking out of mouth. Other signs to look out for include, "respiratory depression, sedation, behavior changes (quieter than usual, more depressed or even aggressiveness or agitation), bradycardia (slowed heart rate), changes in pupil size, urine dribbling, hypersalivation, vomiting, decreased blood pressure, hypothermia, and itchiness," Johnson noted.

If a pet parent suspects their animal has come in contact with opioids, Johnson said immediate medical care should be sought and that they are hospitalized for at least 12 to 24 hours for monitoring and treatment. "Pets with excessively high dose exposure or exposures that result in cardiac arrest and require resuscitation could need longer hospital stays," Johnson said.

While Zoey and her family were lucky, Johnson said that pet parents everywhere need to be as attentive as possible when out for walks and ensure their dogs don't pick up any foreign objects. The same goes for care at home, Johnson pointed out. "Make sure to keep all medications out of reach of pets."